A carbon nanotube is a microscopic, hollow filament comprised of carbon atoms arranged in the shape of a cylinder. Carbon nanotubes are typically on the order of nanometers in diameter but may be produced with lengths of up to several hundred microns. Carbon nanotubes possess high electrical and thermal conductivities in the direction of the longitudinal axis of the carbon nanotubes. Individual carbon nanotubes have displayed thermal conductivities of 3000 W/m-° K and higher at room temperature.
It is known to use composites of aligned carbon nanotubes and a polymer matrix in thermal management applications. Examples of such composite used for thermal applications are found in U.S. Pat. No. 6,428,890 to Ting and in published U.S. Patent Applications 2006/0279191 to Gohegan et al and 2007/0116626 to Pan et al. The present invention relates to improved composite materials made from carbon nanotubes and a polymer matrix including continuous tapes of such material as well as to methods of their production. In addition, the present invention relates to a method of increasing unidirectional heat conduction from a work piece.